WO2005028901A1

WO2005028901A1 - Auxiliary unit drive for a vehicle engine, comprising a couplable and uncouplable pulley, and auxiliary unit

Info

Publication number: WO2005028901A1
Application number: PCT/DE2004/002090
Authority: WO
Inventors: Michael Schütte
Original assignee: Plastech Engineering Gmbh
Priority date: 2003-09-17
Filing date: 2004-09-17
Publication date: 2005-03-31
Also published as: DE112004001764D2; CN1882793A; JP2007506044A; EP1668268A1

Abstract

The invention relates to an auxiliary unit drive for a vehicle engine, comprising a couplable and uncouplable pulley (20) that generates the transfer of torque from a belt guide to a shaft (9), in the coupled state, by means of a friction clutch (22, 12), and can be positioned in such a way that it rotates coaxially about the shaft (9) in the uncoupled state. The friction clutch is thus created by the fact that an active friction driver (16) of the pulley (20) is guided in an axially displaceable manner and is pressed onto a corresponding passive friction driver (11) of the shaft (9) for the coupling. The aim of the invention is to produce such drives in a smaller, lighter, more cost-effective and mechanically simple manner. To this end, the axial displacement of the active friction driver (16) causes a corresponding axial displacement of the ring guide.

Description

Auxiliary unit drive for a vehicle engine with a belt pulley that can be connected and disconnected, as well as an auxiliary unit

The invention relates to an auxiliary unit drive for a vehicle engine with a belt pulley that can be coupled and uncoupled, and an auxiliary unit. More specifically, the invention relates to the drive with respect to the one in which the pulley in the coupled state produces a torque determination of a belt guide to a shaft via a friction clutch and which is rotatably mounted coaxially around the shaft in the decoupled state, the friction clutch generally being produced thereby that an active friction driver of the pulley is axially displaceable and is pressed onto a corresponding passive friction driver of the shaft for coupling. With regard to the auxiliary unit, the invention relates to one with a unit housing, a shaft, a unit active device arranged on the shaft and a rotatably mounted pulley, which is designed so that it can be connected and disconnected to or from the shaft by means of a coupling.

An auxiliary unit drive is known from EP 0 136 384 A2, which taps the rotation of an engine crankshaft by means of a belt. On the crankshaft of the engine there is a belt pulley which drives several auxiliary units via one belt. In this construction, a water pump, a cooling compressor, an air pump, the alternator and the power steering of a vehicle are driven as auxiliary units. So that these auxiliary units do not have to be moved when the engine is started, the pulley on the crankshaft has an electrically switchable coupling; the components required for this are arranged inside the pulley and partly on the shaft. As soon as the engine has started, the auxiliary units are switched on. However, the construction of such a pulley is quite complicated and the clutch mechanism is correspondingly expensive.

[03] EP 0 416 492 B1 shows a continuously variable transmission with continuously variable pulleys. In one of the belt pulleys, a spline toothing is provided on an axially projecting sleeve section, which can be coupled and uncoupled to an inner spline toothing of a sleeve by axial displacement of the sleeve. Such a coupling process can, however, only take place at a standstill. [04] DE 42 43 777 AI proposes an auxiliary unit drive in which a friction clutch connection between a belt pulley and a torque plate fastened to an assembly shaft takes place through a displaceable counterpart of the clutch housing. The displaceable counterpart is arranged with an axial toothing depending on the rotation of the pulley, but is axially displaceable independently of this. An annular slot is formed between the sliding counter pulley and the belt pulley, within which the torque pulley of the shaft is positioned. To couple the shaft to the pulley, the displaceable counterpart is pressed in the direction of the pulley, as a result of which the torque disk of the shaft is clamped in the narrowing slot between these two elements and causes the moment to close. In the recoupled state, the shaft is carried along in a step-down gear with the rotation of the pulley.

[05] Further auxiliary unit couplings and related proposals can be found in DE 195 29 073 Cl, DE 101 55 458 AI, US 2 107 341 and DE 19641 507 Cl.

The object of the present invention is to improve an auxiliary unit drive or a driven auxiliary unit in such a way that they can be made smaller, lighter, less expensive and mechanically simpler.

[07] According to a first aspect of the invention, this object is achieved by a generic auxiliary unit drive in which an axial displacement of the active friction driver causes a dependent axial displacement of the belt guide.

[00] Such a solution allows the pulley to be switched during operation with particularly simple means, so that, for example, the starting process of an internal combustion engine is not burdened with additional torque resistances. In addition, the distances required for switching the friction clutch are relatively short, so that fast switching operations can be achieved. In particular, depending on the short switching path required, the dependent axial displacement of the belt guide can also be carried out correspondingly briefly. A critical shifting of the belt or a critical twisting or twisting of the belt is therefore not to be feared. In addition, the clutch condition inside the auxiliary unit drive can also be read from the outside by the position of the belt guide.

[09] All of these advantages are moreover possible according to the presented aspect of the invention by a simple mechanical design, so that, in contrast to electrically switching clutches such a variant can also be attached to the auxiliary units themselves. In any case, the frictional engagement between the active friction driver and the passive friction driver serves as a mechanical torque transmission device between the pulley and the shaft.

[10] Conceptually it should be explained that the friction clutch does not have to guarantee the transmission of torque exclusively via friction. Rather, most designs of friction clutches will also result in at least microscopic canting and / or wedging at the end between an active and a passive friction mimic. It is characteristic of a friction clutch in the sense of the present application that when the active friction driver is brought up to the passive friction driver, the moment lock does not increase extremely suddenly, but can be increased continuously or in several steps. This is an essential prerequisite for ensuring that all components are protected as best as possible when the auxiliary unit is coupled to the drive torque and can therefore work permanently. Irrespective of this, the switching operations can also take place very quickly if this is possible on the one hand and is also desired on the other hand. In this respect, a friction clutch can also be suddenly engaged and closed if necessary.

[11] The belt filler is the component that actually receives the belt and, in particular, axially guides it. The belts considered here are usually poly-V belts or simple V-belts, so that a corresponding belt filler range will include a complementary poly-V profile or a simple V-profile.

[12] The differentiation between the active friction driver and the passive friction driver assumes that only one of the two drivers interacting in the frictional engagement is moved in order to switch between the coupled and the decoupled state, or that at least one of the two drivers does more or significantly more than the passive driver moves or is actively driven to engage or disengage. In order to keep the contraction as simple as possible, it is preferred if the passive friction driver is axially fixed.

[13] The "pressing" of the active friction driver onto the passive friction driver is precisely the mechanical action which at least essentially effects the frictional engagement between the drivers and thus the coupling of the auxiliary unit drive. The transmissible torque at the moment engagement between the two friction drivers becomes in most Cases depend directly on this, at least within reasonable operating parameters such as the pressing force. [14] As has already been explained, the active frictional medium is displaced axially along the shaft in order to achieve the frictional locking and thus the coupling. According to the presented aspect of the invention, the belt guide is also axially displaced with respect to the shaft when the active friction driver is moved.

[15] The active friction driver is preferably set such that it opposes a restoring force or a restraining force against an end with the passive friction driver or a shift to the passive friction driver Irin. The restoring force can be provided, for example, by a suspension which exerts an axial force on the active friction driver as soon as it is shifted from a zero position to the passive friction driver, with no frictional engagement between the friction drivers being present in the zero position. The restraining force can be achieved, for example, by a specific bearing arrangement of the active friction driver in such a way that it must first overcome a holding force for any axial displacement. This can be provided with simple means by a weak clamping fit of the active friction driver or by a sliding surface with increased static friction compared to the other material of the driver. The advantage of both mechanisms is that with a suitable design, energy only has to be used to actuate the clutch, that is to say to activate or open the frictional engagement. This makes it easier to carry out the entire clutch construction in a purely mechanical manner in such a way that in the engaged or disengaged state, energy does not have to be applied to maintain one of these states.

[16] Alternatively and cumulatively, the present invention proposes, according to a further aspect, to cheapen and simplify an auxiliary unit drive for a vehicle engine with a belt pulley that can be coupled in and uncoupled, which, in the coupled state, produces a torque connection of a belt guide to a shaft and that in the decoupled state is mounted coaxially rotatable about the shaft, before the belt guide in the decoupled state is rotatably mounted about the shaft irrespective of a rotation.

[17] DE 42 43 777 AI has a constant entrainment between the belt guide and the shaft in a load gear and a gear ratio. According to the knowledge in accordance with this second aspect of the invention, however, a stocky carrying is not necessary in many cases. It is often sufficient to be able to switch between a complete and a completely uncoupled state. Due to the short switching travel, the auxiliary unit can also accelerate against its inertia in a sufficiently short time. It has also been shown that the wear between the two friction drivers when moving together their two surfaces is not significantly mine must be as when moving together the active driver surface rotating under load speed with the initially still passive driver surface.

According to a third aspect of the invention, it is proposed that the active friction driver be arranged on one side of the passive friction driver and that a frictional engagement takes place exclusively between the active friction driver and the passive friction driver.

[19] This idea of the invention makes it possible, in particular, to make the auxiliary unit drive axially very short. The passive friction driver can be, for example, a torque disk on one end face of the shaft. Due to the one-sided arrangement of the entire friction clutch mechanism, it can be accommodated completely in the surrounding space around the shaft. Thus, the shaft can be made as short as possible, and yet it is not necessary to provide additional components of the auxiliary unit drive beyond the required length of the shaft.

[20] In a preferred embodiment of an auxiliary unit drive according to the invention, the belt guide is axially fixedly connected to the active friction driver. This can go so far that the belt guide is made in one piece with the active friction driver, for example by means of a one-piece design of the belt guide and the active friction agent on the belt pulley. In this case, the belt belt and the active friction driver form very important elements of the belt pulley. An axially fixed connection makes it possible to dispense with any translation means. It goes without saying that the one-piece variant is particularly inexpensive and mechanically simple. As a result, the overall assembly of the auxiliary unit drive is not only extremely cost-effective, but is also very wear-resistant.

[21] In order to make the auxiliary unit drive or at least its essential elements spatially compact, the belt guide can be arranged radially immediately outside the active friction driver. The other way around, in this case, the active friction driver can be accommodated in the radial free space within the belt guide and thus during operation within the rotating belt. This optimally utilizes the space within the belt that is olmeliin's dead space for other units in the vehicle drive.

Such an arrangement can be realized not only on an auxiliary unit drive according to the previously presented aspects of the invention, but also on an auxiliary unit drive in which the active friction element can be axially displaced with respect to the shaft and the belt guide or a belt guide element which, however, the belt guide body, preferably the entire belt guide, together with the active friction driver are arranged axially on one side of the passive friction driver.

[23] According to this aspect of the invention, the construction already explained on one side of the passive friction driver can also be used if the active friction driver is axially displaceable with respect to the shaft and the belt guide or a belt guide element. In such an embodiment, the belt guide does not shift depending on an axial displacement position of the alcüven friction meter. A disadvantage of this type of construction is that a two-piece construction between the belt guide and the active friction driver is required. Depending on the intended use, however, this can be accepted or can be advantageous, since if the alcüven friction driver wears out, it can be replaced depending on the residual construction phase. In addition, the contraction of the auxiliary unit drive can react flexibly to new developments in materials for friction drivers without having to influence the belt guide. In addition, or as an alternative to the aforementioned advantages, relatively large belt forces can then be countered by the belt guide, without this hindering an axial displacement of the active friction driver. With an axial coupling this is at least only possible to a limited extent and not possible with a one-piece design.

[24] One-sided execution of the clutch mechanism with respect to the passive friction driver is facilitated if the passive friction driver is arranged on a stiffened ring plate on the shaft.

Regardless of which of the aspects of the invention the auxiliary unit drive is designed, it is advantageous if the alctive friction driver is mounted radially on the inside. The alctive friction clutch is a component that transfers considerable forces and moments from the drive to the output. Its position is therefore to be carried out with great care and stably. This requires a particularly firm bearing. If the alctive friction driver is mounted radially on the outside, a rather solid housing must therefore be placed around it, which unnecessarily increases the auxiliary unit drive. The bearing of the alcüven friction driver towards its radial inside leads to a direct or indirect force dissipation to the shaft, which is not critical. In addition, the required outer circumference of the auxiliary unit drive is considerably smaller.

The same applies if the pulley is mounted radially on the inside. [27] Cumulatively or alternatively, an auxiliary unit drive for a vehicle engine with a belt pulley which can be coupled and uncoupled, which in the coupled state produces a torque connection of a belt guide to a shaft mounted on a housing via a friction clutch and which can be rotated coaxially around the shaft in the decoupled state is supported, in which the friction clutch is arranged radially and / or axially outside the housing. Such an arrangement makes it possible to minimize the changes to an already existing auxiliary unit or housing in order to implement the present invention. Since the corresponding shaft already penetrates the housing in order to interact with a pulley, essentially only a bearing for the pulley needs to be provided outside the housing. The overall installation space can thus also be minimized, as was already explained above with regard to the dead space. There is then also the possibility, in addition or as an alternative to the aforementioned advantages, to actuate the friction clutch and its construction groups to be shifted directly from outside the housing, which considerably simplifies the integration of the unit drive into an overall arrangement.

[28] The shaft can preferably be mounted radially inside a bearing bush of the housing and the belt pulley radially outside the bearing bush. This considerably simplifies the arrangement, since the bearing bush can be used twice and unnecessary space loss can be avoided.

Accordingly, individual sections of the pulley, such as the friction clutch, the belt guide, an active friction driver or a pulley edge body can be mounted radially outside, in order to achieve the advantages described above, if not possibly to the extent that all the sections are radial and / or are stored axially outside.

[30] A rear-supported gear ring is preferably proposed for pressing the alcüven friction driver onto the passive friction driver. The auxiliary unit drive or a corresponding housing supporting the shaft anyway has numerous rotationally symmetrical components, so that a ring can be molded onto it with minimal space requirements. Thus, a radial fixation of the clutch drive is automatically guaranteed. Only care must be taken for an axial force to press the friction drivers against each other. For this, the rear support is seen. It goes without saying that the bearing against which the gear ring is supported at the rear is preferably also rotationally symmetrical.

[31] The overall structure of the auxiliary unit drive is also further simplified by the fact that, on the one hand, the direct integration of the individual construction steps with a one-part filling order Positioning methods can be used in which the required construction steps are already formed during the production of the blank, for example by casting processes.

[32] So that the axial friction driver or - depending on the specific design - the entire pulley can or can be axially displaced easily and with little wear, it is proposed that it be arranged on an axially displaceable bearing. In many cases, due to the short switching paths that are generally required for friction clutches, it is not even necessary to create compensating devices for the belt to skew. In particular, the overall arrangement can be designed in such a way that the belt is only slightly inclined in the unloaded state, ie in the uncoupled state. Otherwise, appropriate compensating means can also be provided for an inclined position of the belt if the desired service life requires it.

[33] An adjustment mechanism for the relative axial displacement of the belt guide, the belt pulley and / or the alcüven friction driver is preferably provided. According to one variant, the adjusting mechanism can have an adjusting belt with ramp-shaped toothing on the end face and a fixed adjusting device with complementary ramp-shaped toothing, wherein the ramp-shaped toothing can be designed in such a way that an axial displacement of the adjusting ring and / or. Relative to one another by rotating the adjusting ring and the adjusting device the adjustment takes place. A rotary movement is accordingly converted into an axial movement, the rotary movement being able to take place entirely as a function of a rotation of the shaft and / or the belt guide. By suitable selection of the ramp-shaped toothing, high forces can be achieved with a relatively narrow installation space and nevertheless sufficient axial displacement. The rotary movement can be initiated, for example, by an under-pressure socket, a servo or a similarly acting component. It is also possible to use a thread for adjustment, for example a trapezoidal thread.

[34] A particularly advantageous design to achieve the axial movement provides that the axially displaceable bearing is a rolling element bearing with an inner and outer ring and rolling elements arranged therebetween, the adjusting mechanism having a clamping device which, in the coupled state, has the inner ring of the rolling element bearing clamped to transmit the drive torques. The force is therefore applied to the inner ring of the rolling element bearing, and the entire bearing can be moved using the belt guide or the alcüven friction driver. The position can be specified precisely by firmly sealing the inner ring in the coupled position. [35] Furthermore, the clamping device can be formed by spring rings arranged on both sides of the inner ring of the rolling bearing. This has several advantages. On the one hand, the clamping force can be determined precisely in this way. On the other hand, there is a vibration coupling through the sprung arrangement. This ensures that the auxiliary unit drive runs very quietly in the coupled state. The clamping device can also be designed in such a way that a certain clamping force is still present in the uncoupled state, as a result of which vibrations can also be reduced in this state.

In particular with regard to filling the auxiliary unit drive according to the fourth aspect of the invention, according to which the belt guide element and the active friction element are arranged axially on one side of the passive friction element, it is proposed in a further embodiment that the active friction element is located in axially extending recesses in the belt guide. basic body lies. The recesses in the belt guide base body are openings in which the active friction carrier lies and through which or from which it is pressed onto the passive friction carrier for coupling. Such a configuration places less demands on the position of the belt pulley edge body itself, since axial forces can be transmitted to a large extent directly via the active friction medium. The arrangement of the active friction driver in axially extending recesses in the belt guide grand body enables a rotational driver device to be created without further steps, which transmits the torque between the coupled alcüve friction driver and the main pulley body.

[37] Especially with such an embodiment, the adjustment mechanism for the alcüve friction driver or the belt guide can have an elastic clamping device which, in the coupled state, clamps the driver constellation between the active friction sensor and the belt guide for transmitting the drive torques. The driver constellation is thus ensured by a spring force on the friction surface of the passive friction driver. This causes a further vibration coupling.

[38] The axial power transmission loads the belt guide or the belt belt element particularly little if the active friction driver axially completely penetrates the belt shaft element. In a particularly preferred embodiment, the active friction mower has for this purpose a plurality of dislcrete friction bodies along the circumference, the end faces of which rub against the friction Use the passive friction medium to close the exercise when the auxiliary drive is switched on.

[39] An advantageous variant provides that the belt pulley main body and / or the active friction medium is rotatably and axially displaceably mounted on an outer peripheral region of the auxiliary unit housing. The belt pulley body becomes an integral part of the auxiliary unit. This clearly stipulates that it is not the driving pulley but the pulley of the auxiliary unit itself that can be switched.

[40] This enables in particular the coupling and decoupling of individual auxiliary units. This not only saves energy during the starting process, but also during the entire operation of the vehicle drive, since the auxiliary units can be switched on and off individually or in grapples as required.

[41] A constructive simplification provides that the adjusting device of the adjusting mechanism is part of the auxiliary unit housing. In particular, a ramp-shaped toothing can then be molded directly onto a corresponding area of the auxiliary unit housing, so that additional components are not required. Here, for example, plastic technology can also be used, so that, for example, the ramp-shaped toothing is formed directly during a spraying process. Such training can also be carried out using suitable casting processes.

So that in each of the proposed embodiments an effective clutch effect is given and the friction surface is increased, according to one embodiment, friction surfaces on the alcüve friction clutch and or on the passive friction clutch are formed by a plurality of coaxially arranged circular or annular segment-shaped toothing grooves, the friction surface on the passive friction clutch being complementary Has toothed grooves on the friction surface on the alcüven friction medium. In the coupled state, these toothed grooves engage with one another with their flanges. Depending on the design of the groove shape in cross-section and in the circumference, the contact pressure can be increased. The tendency to wear is also reduced due to the increase in the friction surface.

[43] A particularly cost-effective variant provides that the pulley base body, the belt guide and / or the active friction screw is or are made of a plastic material. With the help of common chemical processing methods, the belt pulley Bengrandlcöφer and the alctive Reibungsmiüiehmer can be produced in one manufacturing process, if desired, different materials can also be used, for example by coinjection molding. There is also the possibility to use a metal or ceramic material.

[44] In order to improve the service life of the unique torque clutch, the alctive and the passive friction clutch can have a friction lining. This friction lining absorbs the heat generated during the initial ratcheting during the shifting process and also considerably increases the coefficient of friction.

[45] The toothing grooves and / or the complementary toothing grooves of the alcüve friction follower or of the passive friction follower can advantageously be arranged in the friction lining, as a result of which this can also have its effect in the flange area of the toothing grooves.

[46] It is also advantageous if, according to a variant, active agents are arranged on the shaft which, when coupled, rotate in the auxiliary unit housing. The active means driven by the pulley are therefore located directly in the auxiliary unit housing, as a result of which a very compact structural unit can again be obtained. This can involve a wide variety of active agents, which together with the shaft form a rotor, which is generally in operative relationship with the unit housing.

[47] The unit housing is preferably a pump housing and, accordingly, the active agents are preferably a pump wheel. In auxiliary units on an internal combustion engine, pumps such as water pumps, air pumps, air conditioning compressors, power steering pumps, etc. are very often used. If these are each equipped with a switchable belt wheel, they can be switched on and off as required. In this way, the power losses of the internal combustion engine can be significantly reduced.

According to a further aspect of the invention, this relates to an auxiliary unit for a vehicle engine, and the auxiliary unit has an unit housing, a shaft, an active agent arranged on the shaft and a pulley which is rotatably mounted on an outer circumference of the unit housing and which is designed to be connectable or disconnectable with or from the shaft by means of a coupling.

For the first time, an auxiliary unit according to this proposal is provided directly with a pulley which is mounted directly on the unit housing and which can be coupled to the shaft of the auxiliary unit in a mechanically actuated manner. In particular, an arrangement can be achieved by a mechanically operated coupling can be found in which, in the switched state - that is, disengaged or engaged, a corresponding actuator, such as a motor, a servo, a magnet or the like, is not under load, but rather that energy only has to be applied for switching operations. It has already been explained that such an arrangement, in which the pulley lies on the outside of the housing, is particularly space-saving. The auxiliary unit can optionally be connected or disconnected while the belt is constantly engaged with the pulley. The engine therefore only has to work on driving the auxiliary unit once it is switched on.

[50] It has already been explained that the invention is distinguished in numerous details by the fact that the pulley is or can become a direct component of a friction clutch. In addition to the cost aspects, which are very important in the automotive sector, this will also make it easier to meet operational safety requirements, since friction clutches represent very simple clutches in terms of their function and structure, in particular compared to the known electrical or mechanically very complex mechanisms.

In view of what has been described above, it is understood that a method for operating an auxiliary unit drive for an internal combustion engine, which has at least one auxiliary unit with a pulley that can be coupled in and out of the shaft of the auxiliary unit, is advantageous, in which the auxiliary unit drive is driven by a pulley connected to the crankshaft of the vehicle engine and a belt which is in engagement with at least one pulley of an auxiliary unit, and in which the pulley is coupled and decoupled to or from the shaft of the auxiliary unit according to at least one predetermined parameter and / or at the choice of an operator. The auxiliary unit drive can in particular be in one of the prescribed configurations.

[52] While in the prior art the crankshaft pulley can be coupled or uncoupled, it is preferred according to this method to remove individual auxiliary units from the drive system when these auxiliary units are not required. This can be of particular interest when using water pumps or cooling compressors.

[53] The present invention is explained in more detail below on the basis of two exemplary embodiments with reference to the drawing. Show it:

1 is a Wasseφumpe as an auxiliary unit of an internal combustion engine with a pulley in full section, with an adjusting ring for initiating a clutch lock, 2 shows the adjustment ring from FIG. 1 in a view from the right (based on FIG. 1),

3 shows the adjusting ring from FIG. 2 in a section along the line III-III in FIG. 2 and

Fig. 4 shows a second embodiment of a Wasseφumpe as an auxiliary unit of an internal combustion engine with pulley in full section.

[54] The Wasseφumpe 1 shown in full section in Figure 1 is arranged as an auxiliary unit on an internal combustion engine not shown and described. The arrangement and grouping of the auxiliary units, including the belt wheels assigned to them and the rotating belt, can be carried out in a similar manner to that in EP 0 136 384 AI. However, the pulley on the crankshaft of the internal combustion engine does not necessarily have to be able to be switched on and off via a clutch.

[55] The belt, also not shown, is a poly-V belt which connects at least the water pump 1 shown to the pulley of the crankshaft.

The Wasseφumpe 1 has a bell-shaped pump housing 2, which is provided with an inlet, not shown, and an outlet, not shown, for the cooling water. The pump housing 2 is preferably attached to a motor block by means of a flange 3, and the pump shaft 4 extends coaxially through the pump housing 2. The pump shaft 4 is rotatable within the pump housing 2 via two roller body bearings 5 and 6 which are arranged at a distance from one another in the pump housing 2 Bearing bush of the housing 2 stored. The bearing bush protrudes from the rest of the housing as a hollow journal and carries the roller bearings 5 and 6 radially on the inside. In the pump chamber 7 of the pump housing 2, a water pump impeller 8 rotates, which sits on a steel hub 9 which is pressed onto the pump shaft 4. Here you can also order the possibility of integrally connecting the water pump impeller 8 to the pump shaft 4 by means of injection molding technology and the like.

[57] In the front area, outside the pump housing 2, the diameter of the pump shaft 4 is reduced and on this reduced section 10 there is a torque disk 11 connected to the pump shaft 4 in a connected manner. The torque disk serves as a friction clutch element and is provided in its upper section on the side facing the pump housing 2 with a plurality of concentric, annular toothed grooves 12. The entire area of the toothing grooves 12 is coated with a friction lining 13, which also simulates the contour of the toothing grooves 12. On the back of the torque disk 12 there are ribs 11 'which can serve as stiffening and / or as fan blades. Such a fan can be an integral part of the driver or also be provided as an additional component on the shaft on the driver. This creates an integral configuration of the fan and clutch or clutch component. Such an arrangement makes it possible, in particular, to operate a fan and a water pump together, which is advantageous for the operation of a water pump of a motor vehicle, regardless of the other features of the present invention. In particular, it is advantageous if the fan and water pump are seated on a shaft or if the fan is formed in one piece with a water pump shaft, since the fan then only runs when the water pump is needed and thus water has to be cooled.

[58] The pump housing 2 has a cylindrical coupling area 14 on the outside of its bearing bush. A rolling element bearing 15, on which a pulley base element 16 is attached, is slid axially on the lateral surface of this coupling area. The Wälzköφerlager 15 has an inner ring 17, an outer ring 18 and a plurality of Wälzköφer 19. The belt pulley body 16 sits firmly on the outer ring 18, so that the belt pulley 20 thus formed can rotate about the coupling region 14 of the pump housing 2.

The outer circumference of the Rieinenscheibengrandlcöφers 16 is provided with suitable receiving grooves 21, which can be engaged with a suitable poly-V belt. On the end face facing away from the pump housing 2, the belt pulley base element 16 is provided with a plurality of annular toothing grooves 22 arranged concentrically to one another, which are complementary to the toothing grooves 12 on the torque disk 11.

[60] On the coupling area 14 of the pump housing 2 there is a locking ring 23, which secures the roller body bearing 15 and thus the Rieinenscheibengrandköφer 16. An annular return spring 24 is arranged between the inner ring 17 of the roller bearing 15 and the locking ring 23. On the opposite side of the inner ring 17 there is an annular drain spring 25. In the coupled position shown in FIG. 1, the inner ring 17 is clamped between the return spring 24 and the compression spring 25, so that the inner ring 17 is held securely and reliably on the coupling area 14 is.

The pulley 20 is axially displaced by means of the adjusting ring 26 shown in FIGS. 2 and 3, which has a ramp-shaped toothing 27 on the side facing the pump housing 2. The pump housing 2 is provided with a complementary ramp-shaped damming at its adjustment region 28 adjoining the coupling region 14. The adjusting ring 26 has an adjusting lever 29 which can be actuated via an eyelet 30. The actuation takes place via 1 t)

suitable means which act on the eyelet 30 of the adjusting lever 29 and rotate the adjusting ring 26 about its axis.

As can be seen immediately in this exemplary embodiment, the friction clutch is produced in that an active friction element, namely the belt pulley edge body 16, with its end face facing away from the pump housing 2 and having the toothing grooves 22, is axially displaceable and for coupling to a corresponding passive friction element , namely the torque disk 11 with its toothed grooves 12, is pressed on, wherein an axial displacement position of the alcüven friction driver correspondingly hosts a dependent axial displacement of the belt filling formed by the receiving grooves 21, since these are integrally formed with one another.

[63] The operation and function of the water pump 1 described above is explained in more detail below.

[64] In the coupled state shown in FIG. 1, the belt pulley base 16 with its toothed grooves 22 is pressed onto the friction lining and thus the toothed grooves 12 of the torque disk 11. The pressure force required for this is applied by the compression spring 25 - thus the belt pulley body not only functions as a belt guide, but also as an active friction minder. This force is reduced again in part by the resilience of the return spring 24. If, for example, an adjusting force of 5 N is applied to the adjusting lever 29, for example by means of a vacuum box, a servo or the like, the lever length of the adjusting lever 29 and the pitch of the toothing increase 27 of the adjusting ring 26 and the toothing of the adjusting area 28 increases this force. The factors of the two adjustment mechanisms are to be multiplied with each other and easily result in the total factor 25. The 5 N given in the example thus result in an axial force of 125 N without taking into account the friction in the cladding. This is the force (eg 25 N) of the return spring 24 to reduce md results in the resulting axial pressing force (eg 100 N). A further reinforcement is provided by the profile of the friction linings or friction surfaces (approx. Factor 3).

[65] It has already been mentioned that the axial displacement takes place by turning the adjusting ring 26 relative to the adjusting area 28, so that in the position shown in FIG. 1 the flat areas 31 of the adjusting ring 26 rest on flat areas of the same configuration on the adjusting area 28 and thus the The maximum distance between the two components is to compress the spring 25 and the return spring 24 in the maximum desired manner. This creates between the teeth tion grooves 22 on the annular disc body 16 and the friction lining 13 of the torque disc 11 a sufficient coupling effect that the belt pulley 20 transmits the desired torque to the torque disc 11 and via this to the shaft 4. As a result, the Wasseφumpeiifl impeller 8 is driven inside the pump housing 2 and cooling water is promoted.

[66] If this pumping process is no longer desired or a predetermined parameter is reached, the adjusting ring 26 is turned back by an eighth of a turn, so that the toothing 27 on the adjusting ring 26 and the complementary toothing in the adjusting region 28 mesh completely with one another and thus together have the lowest overall height ingest so that the springs 24 and 25 are compressed in a minimally desired manner or are no longer loaded. In most cases, a minimum clamping force on the inner ring 17 will still be desired. The axial backward movement (to the right in FIG. 1) of the belt pulley 16 is so great that the toothing grooves 22 are no longer in engagement with the toothing grooves 12 on the torque plate 11 and no more torque is transmitted. The pump shaft 4 and the pump impeller 8 then stand still.

[67] In order for this process to be carried out very easily, the adjusting lever 29 is preferably cranked so that it looks out between the pulley 20 and the pump housing 2.

The return spring 24 and the drain spring 25 also ensure that a low-vibration fastening of the pulley 20 on the pump housing 2 is ensured. This gives the entire Wasseφumpe 1 a very quiet run.

[69] It is obvious that the one-piece construction between the belt guide - embodied by the bearing grooves 21 - and the active friction element with its friction surface 22 results in a direct coupling of any axial movements of these two elements. However, as soon as the clutch is released, the rotation of the belt guide 21 is completely independent of a rotation of the shaft 4.

[70] Both in the coupled and in the uncoupled state, the active frictional element is arranged axially on one side of the passive friction element - embodied by the torque disk 11. The frictional engagement when the auxiliary unit drive 1 is coupled takes place exclusively between the alcüven Reibuiigsπtitnehmer mid and the passive torque plate 11 stiffened to the rear. [71] A second embodiment of the present invention is explained in more detail below with reference to FIG. 4. Insofar as reference is made to components of identical construction or effect, the same reference numerals are used as in the previous exemplary embodiment and reference is made to the above description. Therefore, only the essential differences are discussed in the following.

[72] In this embodiment, the Rieiiei disc-shaped body 16 is not axially displaceably mounted on the coupling region 14 of the pump housing 2. The inner ring 17 of the Wälzlcöφerlagers 15 strikes the safety ring 23. The coupling area 14 is longer in this embodiment since a clutch disk 32 (or driving disk) is pushed onto the clutch area 14. For this purpose, the clutch disc 32 has a corresponding central cylindrical bore. The clutch disc is provided with a plurality of axially forwardly extending coupling projections 33 which extend through corresponding openings 34 in the Rienienscheibengrandköφer 16. On their end face facing the torque disk 11, the coupling projections 33 are each provided with toothed grooves 22 ′ in the form of annular segments. The elevations located next to the toothing grooves 22 ′ can engage in the toothing grooves 12 on the torque disk 11.

[73] The clutch disc 32 is supported towards the inner ring 17 via a plate-shaped return spring 24 '. At the rear 35 of the clutch disc 32 there is an axial roller bearing 36, which is also guided on the clutch area 14. A disc-shaped drain spring 25 'is arranged between the adjusting ring 26 and the axial bearing 36.

[74] The operation and functioning of this second exemplary embodiment are briefly explained below.

[75] As before, the pulley 20 is coupled in and out to the pump shaft 4 via the adjusting ring 26, which is supported on a corresponding counter toothing on the area 28 of the pump housing 2. In the coupled state shown in FIG. 4, the adjusting ring 26 and the area 28 are maximally folded out against each other, so that the return spring 24 'and the spring 25' are in their spring-loaded position. The force transmitted via the axial roller bearing 36 acts on the clutch disk 32, which presses on the torque disk 11 with the ends of its clutch projections 33 and thus effects the torque transmission.

[76] To unlock the adjustment ring 26 is rotated so that it moves to the right and thereby releases the return spring 24 'and the clutch spring 25'. This causes the clutch disk 32 and the Axialwälzköφerlager 36 also to the right and the coupling projections 33 disengage from the torque disk 11.

[77] For the sake of completeness, it should be mentioned that the torque disc 11 can be made of plastic. This results in the possibility that it is sprayed onto the shaft 4 or connected to it in one piece. The friction lining 13 can also be applied in one piece by active substance processing methods.

[78] It can be seen immediately that in both examples the belt guide (outer circumference of the belt pulley gripper body 16 with the receiving rings 21) can be rotated about the shaft 4 in the uncoupled state regardless of a rotation thereof. Also, the active friction element, namely the pulley base body 16 with its end facing away from the pump housing 2 and having the toothing grooves 22, is arranged on one side of the passive friction driver, namely the torque disk 11 with its toothing grooves 12, and a frictional connection takes place exclusively between the active and the passive friction medium.

[79] Furthermore, the pulley 20 can be designed such that the circumferential surface is designed as a flat profile and the expected maximum displacement is spread. The belt, in particular flat belt, would thus remain in its old axial position even when the pulley 20 is axially displaced.

[80] The friction lining can optionally be attached, as shown here, on the rotary disk 11 and / or on the pulley 20.

[81] The Wasseφumpe 1 shown here should only be understood as an exemplary embodiment of an auxiliary unit on an internal combustion engine. The use of a pulley mounted on the unit housing can also be used with Lenlchilf pumps, air conditioning compressors and the like.

Claims

claims:

1.Auxiliary unit drive for a vehicle engine with a lockable and unlockable belt pulley, which in the locked state creates a moment closure of a belt guide to a shaft via a friction clutch and which is rotatably mounted coaxially around the shaft in the unlocked state, the friction clutch being produced in that an active friction element of the pulley is guided axially displaceably and is pressed onto a corresponding passive friction minder of the shaft for coupling, characterized in that an axial displacement of the active friction driver causes a dependent axial displacement of the belt guide.

2.Auxiliary unit drive, in particular according to spoke 1, for a vehicle engine with a lockable and enticoppelbaren pulley, which in the coupled state via a friction clutch creates a moment lock of a belt guide to a shaft and which is rotatably mounted in the uncoupled state coaxially around the shaft, characterized that the belt guide can be rotated around the shaft in the uncoupled state, regardless of a rotation of the shaft.

3. Auxiliary unit drive, in particular according to one or both of claims 1 and 2, for a vehicle engine with a lockable and enticoppelbaren pulley, which in the coupled state via a friction clutch produces a torque connection of a belt guide to a shaft and in the enücoppelten state coaxially around the shaft is rotatably supported, the friction clutch being produced in that an active friction meter of the pulley is guided axially displaceably and is pressed onto a corresponding passive friction meter of the shaft for coupling, characterized in that the active friction meter is arranged on one side of the passive friction driver and that a Friction only occurs between the alcüven and the passive friction medium.

4. Auxiliary unit drive according to claim 3, characterized in that the alctive Reibmitmitnelimer is arranged axially on one side of the passive friction driver.

5. Auxiliary unit drive according to one of the preceding claims, characterized by an axially fixed connection of the belt guide on the active friction medium.

6. Auxiliary unit drive according to one of the preceding claims, characterized by a one-piece design of belt guide and alctivem friction agent on the belt pulley.

7. Auxiliary unit drive, in particular according to one of claims 1 to 6, for a Falirzeug engine with a zu- and enticoppelbaren pulley, which produces a moment lock of a belt guide to a shaft in the coupled state via a friction clutch and which is rotatably mounted coaxially around the shaft in the enücoppelten state The friction clutch is produced in that an active friction minder of the pulley is guided axially displaceably and is pressed onto a corresponding passive friction driver of the shaft for coupling, the active friction medium being axially displaceable with respect to the shaft and with respect to the belt guide and between a Rien enführangs- grandlcöφer and the active Reibmitmitnel a rotational coupling takes place, characterized in that the Riemenführungsangsgrandlcöφer and the active Reibuiigsmitnehmer are arranged axially on one side of the passive friction driver.

8. Auxiliary unit drive according spoke 7, characterized in that the belt guide grandlcöφer and the alctive Reibmitmitnelimer together with the belt guide are arranged axially on one side of the passive friction driver.

9. Auxiliary unit drive according to one of the preceding claims, characterized in that the belt guide is arranged radially immediately outside the active friction driver.

10. Auxiliary unit drive according to one of the preceding claims, characterized in that the passive Reibuiigsmitnehmer is arranged on a stiffened washer on the shaft.

11. Auxiliary aggregate drive according to one of the preceding claims, characterized in that the active friction medium is mounted radially on the inside.

12. Auxiliary unit drive according to one of the preceding claims, characterized in that the pulley is mounted radially on the inside.

13. Auxiliary unit drive, in particular according to one of claims 1 to 12, for a Falirzeugmotor with a zu- and enticoppelbaren pulley, which in the coupled state via a Friction clutch produces a moment closure of a belt fill to a shaft mounted on a housing and which is rotatably supported coaxially around the shaft in the decoupled state, characterized in that the friction clutch is arranged radially outside the housing.

14. Auxiliary unit drive, in particular according to one of claims 1 to 13, for a Falirzeug engine with a zu- and enticoppelbaren pulley, which in the coupled state via a friction clutch raiig a torque filling raiig to a shaft mounted on a housing and the coaxial in the recoupled state is rotatably mounted about the shaft, characterized in that the friction clutch is arranged axially outside the housing.

15. Auxiliary unit drive according to one of claims 13 or 14, characterized in that the shaft is mounted radially inside a bearing bush of the housing mid the belt filling, an active friction driver, a Riemenscheibengrandköφer or the pulley radially outside the bearing bush.

16. Auxiliary unit drive according to one of the preceding claims, characterized by a rear-supported gear ring for pressing the active on the passive Reibmitmitnelimer.

17. Auxiliary unit drive according to one of the preceding claims, characterized in that the pulley, the alctive Reibuiigsmitnehmer and / or a Riemenscheibengrund- lcöφer is or are arranged on an axially displaceable bearing.

18. Auxiliary unit drive according to one of the preceding claims, characterized in that an adjusting mechanism for the relative axial displacement of the pulley, the belt guide, the alcüven friction driver and or a pulley basic element is provided.

19. Auxiliary unit drive according to claim 18, characterized in that the adjusting mechanism has an adjusting ring with stiπ-side ramp-shaped interlocking and a fixed adjusting device with complementary ramp-shaped interlocking and the ramp-shaped interlocking is designed in such a way that by rotating the adjusting ring and the adjusting device is axially displaced relative to one another of the adjusting ring and / or the adjusting device.

20. Auxiliary unit drive according to one of claims 17 to 19, characterized in that the axially displaceable bearing is a roller body bearing with inner and outer ring and roller bodies arranged therebetween and the adjusting mechanism has a clamping device which, in the coupled state, transmits the inner ring of the roller body bearing the drive torque is stuck.

21. Auxiliary unit drive according to claim 20, characterized in that the clamping device is formed by spring rings arranged on both sides of the inner ring of the roller body bearing.

22. Auxiliary unit drive according to one of claims 1 to 16, characterized in that an adjusting mechanism for the relative axial displacement of the belt pulley, the belt guide, the alcüven friction driver and / or a pulley basic element is provided and the adjusting mechanism has an elastic clamping device which is coupled in Condition of the active friction drive to transmit the drive torques.

23. Auxiliary unit drive according to one of the preceding claims, characterized in that the alctive Reibmitmitnelimer lies in axially extending recesses in the belt guide grandlcöφer.

24. Auxiliary unit drive according to spoke 23, characterized in that the alctive Reibmitmitnelimer the Riemeiifül rangsgrandlcöφer completely penetrates axially.

25. Auxiliary unit drive according to one of the preceding claims, characterized in that the active friction medium circumference comprises a plurality of dislcrete friction bodies.

26. Auxiliary unit drive according to one of the preceding claims, characterized in that the belt pulley, the belt guide, the active friction element and / or a belt pulley body is rotatably and axially displaceably mounted on an outer peripheral region of a unit housing.

27. Auxiliary unit drive according to claim 26, characterized in that an adjusting device of an adjusting mechanism 'is part of the auxiliary unit housing

28. Auxiliary unit drive according to one of the preceding claims, characterized in that a friction surface of the active friction driver and / or the passive friction driver is formed by a plurality of annular or annular segment-shaped toothing grooves which are arranged coaxially to one another and, in the case of such a configuration on both sides, the friction surface of the passive one Friction follower has toothing grooves complementary to the friction surface of the active friction follower.

29. Auxiliary unit drive according to one of the preceding claims, characterized in that the pulley, the belt guide, a basic pulley body, the active friction medium and / or the passive friction medium is or are made from a plastic material.

30. Auxiliary unit drive according to one of the preceding claims, characterized in that the active and / or the passive friction catch has or have a friction lining.

31. Auxiliary unit drive according to claim 30, characterized in that toothed grooves and complementary toothed grooves are arranged in the friction lining.

32. Auxiliary unit drive according to one of the preceding claims, characterized in that active agents are arranged on the shaft, which rotate in an auxiliary unit housing in the coupled state.

33. Auxiliary unit drive according to one of the preceding claims, characterized in that on or on the shaft, a torque disk, a passive friction means and / or active agent are integrally connected to the shaft, preferably by plastic molding processes.

34. auxiliary unit drive according to one of the preceding claims, characterized in that an aggregate housing is a pump housing and a pump wheel is provided as Wirlαnittel.

35. Auxiliary unit for a vehicle engine, with a unit housing, a shaft, an active agent arranged on the shaft and a pulley rotatably mounted on an outer peripheral region of the unit housing, which is designed to be coupled to and decoupled from or with the shaft by means of a clutch.

36. The procedure for operating an auxiliary unit drive according to one of claims 1 to 35 for a vehicle engine, which has at least one auxiliary unit with a pulley that can be locked in and out of the shaft of the auxiliary unit, with the following steps:

- Driving the auxiliary unit drive via a pulley connected to a crankshaft of the vehicle engine and a belt which is in engagement with at least one belt guide of an auxiliary unit

- Coupling and Enticoppeln the belt filling to or from the shaft of the auxiliary unit according to at least one predetermined parameter and / or at the choice of an operator